Stuart Kuttner, the paper’s managing editor, said: "It is correct that two journalists have been suspended during an investigation into allegations that they have been selling stories to rival newspapers.

"Obviously if these allegations are shown to be true we will take an extremely serious view."

The investigation is ongoing.

Fitzmaurice has worked for the NoW at weekends for nine years. He also runs his own freelance news agency, Dotcom News, mainly supplying stories overseas.

He had informed the company of his activities in writing and received approval and is said by colleagues to have been shocked to have been confronted with the allegations. He is believed to have written to the company asking for more information.

Eisen has referred his dispute to the NUJ.

It is not the first time national newspaper journalists have been accused of selling stories to rivals. The last decade has thrown up a number of cases, particularly involving tabloids.